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E. Lundgren:
"Cross-sectional STM on III-V semiconductors: ferromagnetic semiconductors, quantum dots and nano wires";
Vortrag: Seminar Institut für Allgemeine Physik (IAP), TU Wien; 14.06.2005.

In recent years, nanostructure technology involving III-V semiconductors have made significant progress. A number of new materials and nanostructures have been invented, most of them being of a very dilute character or extremely small. Because of these properties, their structural characterization on an atomic scale is not straight forward using conventional diffraction techniques.
One complementary technique for structural characterization is so-called cross-sectional Scanning Tunneling Microscopy (XSTM). Here, the III-V semiconductor is cleaved perpendicular to the (100) growth direction resulting in the exposure of the (110) surface. This cleavage procedure enables a sharp STM tip to probe the atomic details of the structure of interest, resulting in important information on the chemical composition as well as on various defects present in the artificial structures..
In this talk results from three different III-V structures with significant technological interest will be presented. The first being the atomic scale structure of dilute ferromagnetic semiconductors superlattices consisting of alternate layers of GaAs and GaMnAs with different compositions. The second example concerns stacked quantum dots of InAs in InP and the last example concerns free standing objects such as nanowires.